Stacking means for products

ABSTRACT

Disclosed is a stacking element for shipping or storing, in which products are stored in stacked layers, each layer including a batch of products, the stacking unit including a plurality of trays one above the other, the sizes of the trays being compatible with the dimensions of a standard shipping pallet. Each tray has a rectangular base on which products can stand, as well as side walls, extending from the perimeter of the base and perpendicular to it, and at least one wall works as a door which can be opened for allowing side introduction of the products in the tray, or closed. Also disclosed is a corresponding tray.

The current invention belongs to the domain of products handling for shipping or storing. The products may be bottles, cans or other containers for liquid. The object of the present invention is a stacking means and a corresponding tray.

The complete product treatment process comprises steps like product filling, labelling, closing, drying, grouping, casing or overwrapping, etc. In order to ensure a high flexibility, it is sometimes desired to have an intermediate product storage. Similar products are stored together, and later extracted for a specific order fulfilment. The subsequent process steps can therefore further treat simultaneously or sequencially different types of products, which gives a better flexibility to the whole processing line.

In this context, there is a need for a solution for storing independent products, which means products not grouped as a pack or in a case, crate, or box.

GB1347005 proposes a flat plate, on which products stand thanks to corresponding referencing cavities, their neck extending through said plate. However, this plate is not enough flexible in terms of compatibility with other kinds of products because its design is specific to the product dimensions. Also, the products can only be inserted from the top, because of the cavities they have to come in.

WO2013116271 further discloses trays, the design of which fits again only one product.

FR2679878 proposes a tray made of a receiving box, and a covering lid. The lid has referencing grooves, to cooperate with the top of the bottles standing on the box itself. The same drawback exists in terms of flexibility, as this lid is adapted to a single product design. Furthermore, the palletizing process needs to handle two different parts, leading to a stacking process less time efficient.

FR2368414 proposes a set of elements comprising a rectangular basket, and a removable flat bottom, as well as a bottom grid and a top lid. This leads again to a palletization process with too many different items to handle. Also, the basket and the lid cooperate directly with the top of the bottles for stabilization. A consequent problem is that the standing products are not stable enough to guarantee a stable stacking.

US2003/0029140 also discloses trays like boxes, closed with an upper lid. Each tray rests on the one underneath, which may lead to tray crushing if the number of layer becomes significant, especially when this solution is used for handling filled up products.

WO2013178226 proposes a product box design, comprising two referencing plates and a set of spacers between them. The products are then stored in a horizontal manner. Here again, the number of elements to handle during the palletizing process is quite high and products need to be precisely inserted in the referencing plates. Also, process efficiency is reduced because of the shift from a vertical position of the products, upstream the palletisation, to a horizontal storing position, and then back to a vertical position downstream to palletization.

In this context, the invention aims at improving this prior art by proposing a storing solution for independent products, flexible in terms of types of products compatible therewith, leading to a stable stack products, with an efficient stacking process.

In order to reach this, the invention proposes a stacking means using tray with a flat bottom surface, and a side wall acting as door, through which, when opened, products can simply be swept from or to said bottom surface.

According to the invention, there is provided a stacking means for shipping or storing, in which products are stored in stacked layers, each layer comprising a batch of products, said stacking means comprising a plurality of trays one above the other, the sizes of said trays being compatible with the dimensions of a standard shipping pallet. This device is characterized in that each tray has a rectangular base on which products can stand, as well as side walls, extending from the perimeter of said base and perpendicular to it, and at least one wall works as a door which can be opened for allowing side introduction of the products in the tray, or closed.

There is also provided a corresponding tray.

Further features and advantages of the present invention will be better understood from the description of preferred embodiments, which is given below by way of a non-limiting illustration, with reference to the accompanying drawings, in which:

FIGS. 1 and 2 show a tray with the door separated therefrom;

FIG. 3 shows a stack of trays, according to the invention;

FIG. 4 shows a detail for operating the straps.

A first object of the present invention is a stacking means 1 for shipping or storing, in which products 2 are stored in stacked layers, each layer comprising a batch of products 2, said stacking means 1 comprising a plurality of trays 3 one above the other, the sizes of said trays 3 being compatible with the dimensions of a standard shipping pallet 4.

A standard pallet 4 corresponds to a rectangle surface of approximately 1 meter side. Products 2 to be stacked are normally elongated products 2, like bottles, can, flasks, etc. The stacking means 1 is for receiving products 2, and comprises a plurality of trays 3, which may be superposed, piled one above the other. The stacking means 1 serves for organizing products 2 in layers. In each layer, products 2 are received in one of said trays 3, as a batch.

The stacking means 1 can organize the products 2 in such a configuration of layers of products 2 for products 2 to be stored in a warehouse, or for shipment, or else. The stacking means I is therefore conveyable by driving it from its bottom, for example with a band based conveying means, a trolley, or other vehicle, etc. The outside bottom surface of the tray 3 is flat for an easy conveying.

The trays 3 the stacking means 1 comprises can be loaded with products 2 organised with a free configuration inside said trays 3. This means that the position of a product 2 is not given by the tray 3 itself. Products 2 are freely positioned with respect to each other, and they are not grouped in batches held together, like in cases, packs or crates. The products 2 are independent with respect to each other. In the stacking means 1, each tray 3 can be separated from the other.

According to the invention, each tray 3 has a rectangular base 5 on which products 2 can stand, as well as side walls 6, extending from the perimeter of said base 5 and perpendicular to it, and at least one wall 6 works as a door 7 which can be opened for allowing side introduction of the products 2 in the tray 3, or closed.

The size of the trays 3 is so that only one tray 3 can be received directly on a standard shipment pallet 4. That is to say, in the stacking means 1, due to the sizes, the trays 3 cannot be aside each other in the same layer, but one layer of the stacking means 1 has only one tray 3.

The bottom face of the tray 3 or base 5 is smooth and flat to allow products 2 slippage, thereby allowing a transfer with a mere planar sweeping movement. This sweeping movement drives the products 2 through an aperture 11, otherwise closed by the door 7. This aperture 11 normally starts from the base 5, avoiding any offset in the product 2 movement. This aperture 11 normally extends along an entire side of the base 5.

The tray 3 has at least one side aperture 11, which can be closed by the door 7. The surface of the aperture can be the entire side of the tray 3. In some embodiments, the tray 3 has only one aperture 11 and corresponding door 7. In some other embodiments, the tray 3 has no fixed side walls 6 at all, and each four side wall 6 can work as a door 7.

This at least one door 7 may be entirely removable from the rest of the the tray 3. It is then possible to detach it from the rest of the tray 3. From a general standpoint, according to a possible additional feature, the door 7 is detachable and can be separated from the rest of the tray 3. This allows for example to have a stock of trays 3 and a separate stock of doors 7.

In some embodiments, the at least one door 7 is simply hinged to the rest of the tray 3, and can rotate to an axis parallel to a side of the base 5, or perpendicular to it, for example extanding from a corner of this rectangular base 5. From a general standpoint, according to a possible additional feature, the at least one door 7 is hinged as a flap and rotates to an axis, for example an axis forming a side of the base 5 or forming a perpendicular corner edge of the tray 3.

When the at least one door 7 is open, the corresponding tray 3 can receive products 2 through the corresponding aperture 11, in a movement which is parallel to the base 5 plane, and also to one of its side.

According to another possible additional feature, each tray 3 further comprises a locking means for locking the at least one door 7 in a closed position. This locking means may make use of magnetic forces, for example. The door 7 can also be force fitted in the rest of the tray 3, or snap fitted, etc. This locking means is controllable, and can be locked or released. Once locked, the door 7 cannot be opened by a movement of the products 2 the tray 3 contains. The locking or unlocking can be performed by a robot, for example.

In some embodiments, the locking means is arranged on the door 7 itself, the tray 3 being such that the products 2, once loaded in said tray 3, maintain the door 7 in a closed position, for example with a door 7 of a L section, the vertical portion of which forms the side of the tray 3, and products 2 being received on the other portion of said section, thereby fixing the position of the door 7.

According to another possible embodiment, the tray 3 is provided with position means 8, for positioning two directly stacked trays 3 with respect to each other, said position means 8 comprising a top portion, located at the top of the tray 3, and a bottom portion, located at the bottom of the tray 3, the top portion of the position means 8 of a first tray 3 being able to cooperate with the bottom portion of the position means 8 of a second tray 3 resting on said first tray 3.

The position means 8 allows trays 3 to mate, thanks to the complementary geometry between, on the one side, the top portion of the position means 8, and, on the other side, the bottom portion. This position means 8 prevents movement parallel to the base 5 and may have surfaces cooperating along a plane perpendicular to said base 5.

In some other embodiments of the stacking means 1, it further comprises a bottom pallet 4 on which the stack of trays 3 rests and which is able to cooperate with the bottom portion of the position means 8 of the first tray 3 of said stack. The cooperation between the pallet 4 and the first tray 3 at the bottom of the stack guarantees a fixed position between the pile of trays 3 and the pallet 4. The stacking means 1 then forms an assembly of trays 3, positioned to each other, along with a pallet 4. For this positioning purpose, the pallet 4 may have a shape corresponding to the top portion of the position means 8, as best seen from FIG. 3.

According to another possible additional feature, the tray 3 has ribs 9 located at the outer side of two facing walls 6, for receiving a strap 10 surrounding the stack of trays 3. This strap 10 forms a closed loop in a plane normally parallel to a side of the stacking means 1. It holds the trays 3 together, thanks to its tension. The at least one strap 3 is opened for separating the trays 3 and accessing to the products 2.

In some specific cases, the tray 3 comprises products 2 standing on its base 5, and the walls 6 are such that the above tray 3 rests on the products 2. From a general standpoint, the stacking means 1 is used in a process during which the products 2 conveyed support the vertical pressure of the above weight, and therefore arrive in contact with the base 5 of the tray 3 right above. This means that the overall height of the side wall 6 is normally less than the height of the products 2, in order to avoid transferring the weight of the products 2 directly in the side walls 6 of the tray 3 directly under.

According to another possible feature, the tray 3 has a unique identification means, like an UID tag. This serves for tracking the exact location of each specific tray 3 inside a processing plant. This unique identification means can also be installed on the pallet 4. These identification means are detected by compatible locators of the plant, for example fixed gates or geolocation devices. An information relating to their position is communicated to a controller, which then knows exactly the position of each and every tray 3.

In the embodiment shown in the attached drawings, the stacking means 1 comprises a plurality of trays 3, one on the top of the other. As will be further explained, two successive trays 3 are in contact at least for referencing purposes. The trays 3 are similar, so that the stacking means 1 comprises a plurality of trays 3 of the same design.

The tray 3 has a flat smooth base 5, of a rectangular shape. This base 5 is normally horizontal, and products 2 are freely standing on this base 5. The base 5 is smooth enough for products 2 to easily slip on it. The base 5 is flat on its internal side, for products 2 to stand and easily move on it. In preferred embodiements, the base 5 is also flat on its external side, for resting on a batch of products 2, standing in the tray 3 underneath. The flat surface contributes in a free position of the products 2 with respect to the tray 3, and to compatibility with different sorts of products 2.

At its inner face, the base 5 has no product 2 referencing shapes like ribs, cavities, grooves, etc. Hence, the products 2 can easily move by slipping on the base 5 and stand with a stable position wherever they are.

There is no offset surface tending to move the product 2 to an unstable position. The products 2 are freely organized on the base 5. Products 2 of a cylindrical base can for example be organized with one product 2 slightly inserted in the space between two other products 2 in contact next to it. The tray 3 provides for a bulk accumulation of products 2, independent to each other and freely positioned with respect to each other.

Products 2 have a mainly cylindrical shape, with an axis of symmetry which is normally perpendicular to the base 5. Their shape is normally elongated along the axis of symmetry, so that the size of the base is smaller than their height. Once loaded in the stacking means 1, the axis of symetry is vertical.

The tray 3 has a size corresponding to a standard pallet 4 for shipment, so in the range of a rectangle of one meter side, approximately between 800 and 1200 centimeters.

The single tray 3 or the entire stacking means 1, once loaded, can be conveyed with dedicated conveying means, for example a chain or belt based conveyor, a trolley or other vehicle, guided or autonomous. For example, each single tray 3 can be moved through the processing line on a planar conveyor, a robot, a trolley, etc. It is the same for the stacking means 1, preferably with the pallet 4. To that purpose, and especially for a robot to grip it properly, the tray 3 may present openings compatible with the gripping tool of said robot, or any other shapes easing the gripping, for example undercuts, ribs, grooves, holes, etc.

The tray 3 also has four walls 6, extending from the sides of the base 5 and perpendicular to it. From a general standpoint, these walls 6 define the side limit of the trays 3 and can therefore can be plain or not. For example, walls 6 can be in the form of flat plates, or simply of stops extending along the side of the base 5, at a distance thereof.

The base 5 and the four side walls 6 form a large case or open box in which products 2 are received.

Thanks to the flat and smooth inner surface of the base 5, products 2 can be introduced by a sweeping movement, parallel to said base 5, preferably parallel to a side of the base 5. Therefore, for transferring products 2 from or to an external receiving element, the corresponding tray 3 is simply brought so that the inner surface arrives flush with said receiving element.

For transferring products 2 by sweeping to a flush receiving surface, it is necessary to temporarily remove at least one wall 6. Therefore, at least one wall 6 works as a door 7, which can be in two positions. The first position is the active position: in the active position, the door 7 limits the movement of the products 2 and maintain them on the base 5. The second position is the inactive position: in the inactive position, the door 7 gives access to a side aperture 11 through which products 2 can flow parallel to the base 5.

The door 7 preferably extends along the whole side of the tray 3, giving access to an aperture as wide as the tray 3 itself. In the active position, the door 7 limits the movement of the products 2. In the inactive position, the products 2 can easily move through the accessible aperture 11.

The door 7 can form an entire side wall of the tray 3. In other words, the aperture 11 can extend over the entire side length of the tray 3. The door 7 can be a removable element, which can be attached to the rest of the tray 3 in the active position and detached from it in the inactive position. Removing this door 7 is therefore necessary for inserting products 2 thereon, as well as for taking products 2 out of it.

When the door 7 is in its active position, the tray 3 forms a box, only open at its top, therefore with a flat bottom and four sides extending from it. When the door 7 is in its inactive position, the tray 3 forms a box, open at its top and at a side thereof.

The door 7 can also be permanently fixed to the rest of the tray 3, and simply moved between its two position. For example, the door 7 can be mounted to the rest of the tray 3 with a hinge. This hinge then forms an axis of rotation. This axis can be parallel to the base 5, at a side thereof. It can also be perpendicular to said base 5, extending from a corner of the rectangular shaped base 2.

In some embodiments, the tray 3 has four walls 6, and each wall 6 is hinged to the base 5. This reduces the height of the empty trays 3 once flat, and stacked in a pile of empty trays 3.

For ensuring the stability of the tray 3 whatever the position of the door 7, the tray 3 preferably has at least one wall 6 rigidly fixed to the base 5.

In some preferred embodiments, the tray 3 has four walls 6, one forming the door 7 and the three others being of a fixed position. In some other preferred embodiments, the tray 3 has four walls 6, two of them facing each other and being of a fixed position, the two others also facing each other and working as doors 7. In these last embodiments, products 2 can be transferred from or to the tray 3 through two facing apertures 11.

This stacking means 1 is to be used for forming stacks of layers, each layer grouping a batch of products 2 in a tray 3. Each layer consists of a tray 3. The stacking means 1 can be used to receive products 2 in a palletization process, at the end of a product 2 processing line. Once fully loaded, the stacking means 1 is transferred to a warehouse. The stacking means 1 can also be used in a depalletization process, in which products 2 are taken from it to be later treated in a processing line.

The stacking means 1 comprises a plurality of trays 3, one above the other. As already explained, the base 5 is preferably flat and smooth also at its external outer side. This side comes in contact with the products 2 of the tray 3 directly under. In order to guarantee the relative position of the tray 3, it is proposed that each tray 3 has a position means 8.

This position means 8 works for avoiding any relative movement parallel to the base 5, for two successive trays 3. It is preferably located at the periphery of the tray 3 and works with mechanical engagement. Thanks to this position means 8, each tray 3 is compatible with another one located above it and another one located under it.

The position means 8 comprises a top portion for cooperating with a tray 3 directly above. It also comprises a bottom portion for cooperating with a tray 3 directly under. It goes withtout saying that the bottom portion the position means 8 of a tray 3 is compatible with the top portion of the position means 8 of a tray 3 located directly under. The top portion of the position means 8 can be located at the level of at least one wall 6.

The position means 8 may use pins and holes, or ribs and groove, basically complementary convex and concave shapes. Once the upper portion of the position means 8 of the down tray 3 is engaged with the lower position of the position means 8 of the upper tray 3, the trays 3 are then referenced in position relative to each other. The whole stacking means 1 therefore has a stable structure and shape once the trays 3 cooperate thanks to the position means 8, which reference them in terms of position. Thanks to cooperation of the position means 8, the stacking means 1 works as a stable product 2 rack.

However, it should be noted here that the position means 8 works for creating abutment surfaces between two trays 3, for preventing a movement parallel to the base 5. Preferably, the upper tray 3 does not rest on the down tray 3 at the level of the position means 8. From a general standpoint, it is preferable that the weight of the upper tray 3, along with the other eventual trays 3 stacked on it, is not transferred to the the position means 8 of the lower tray 3.

Preferably, the position means 8 are located at the side of the tray 3. The position means 8 has a embossing portion, and a cavity portion. Preferably, the cavity portion is at the bottom side of the tray 3, and the embossing at the top side. With such a configuration, the tray 3 can stand on a flat surface in a stable way, for example a conveyor.

In some embodiments, the stacking means 1 comprises a pallet 4, and this pallet 4 has a shape able to cooperate with the position means 8 of the first tray 3. In other words, the pallet 4 has the upper portion of a position means 8, able to cooperate with the bottom portion of the position means 8 of the tray 3 directly on it.

It should be noted however that the presence of position means 8 is not mandatory.

Preferably, a wall 6 does not touch the upper tray 3. This means that a tray 3 stands on the products 2 of the tray 3 underneath. The walls 6 do not serve to absorb the weight of the trays 3 above. Said weight can be significant if the base 5 of each upper tray 3 is fully loaded with filled up products 3, like bottles of liquid, for example. As the tray 3 is preferably made of plastic, the wall 6 could not sustain such a significant compression force. The walls 6 define the limits of the surface onto which products 2 can be received, are high enough to avoid products 2 falling, and also preferably receive at least the upper portion of the position means 8. Walls 6 do not serve as a mechanical support for the upper trays 3.

Walls 6 are preferably at least higher than the center of gravity of the products 2. However, it is not necessary that they extend over the top of the products 2, because, as already said, the walls 6 are not supposed to compensate for the weight of the upper trays 3.

It should be noted that when a tray 3 is posed on products 2, said products 2 normally do not go through the base 5 of said tray 3. The base 5 of the above tray 3 simply comes in contact with the top of the products 2 of the tray 3 directly underneath. No specific aperture or opening is needed for a neck of a product 2 as bottle to go through the base 5. In a stacked configuration, the first tray 3 rests on a pallet 4, the other trays 3 rest on the products 2 of the tray 3 directly under.

As already understood from the above description, the base 5 forms the same part cooperating both with the bottom of the products 3 standing on it at a side thereof, and with the top of other products 3 on which it stands, at the other side. The stacking means 1 is therefore comprised of a plurality of trays 3 of a simple design.

Also, to keep the tray 3 simple, it is preferable to have it manufactured with plastic. In preferred embodiments, a single plastic part forms both the base 5 and at least the walls 6 other than the at least on door 7. This single plastic part can be manufactured by injection moulding.

The tray 3 can be so configured that the door 7, in closed configuration, is partly inserted in the rest of the tray 3, preferably in the thickness of the tray 3 itself. For example, in some embodiments, the door 7 has the shape of two perpendicular flanges or plates, therefore having an L section. In such a configuration, one branch of this L shape may be insertable in base 5 itself. This contributes to fixing the position of the door 7 in the closed position.

The tray 3 also has locking means for the at least one door 7 to be rigidly fixed to the rest of the tray 3. For example, this locking means may use a magnet based solution, or a snap fit solution. A locking means may also be a tight mechanical adjsutement between the door 7 and the rest of the tray 3. From a general stand point, the locking means guarantees that the door 7 remains in its position.

Also, for further improving the stability of a set of trays 3 stacked on each other, straps 10 can surround the stacking means 1. With trays 3 oriented along a horizontal plane, a strap 10 would then extend in a perpendicular plane, which is then vertical. The strap 10 forms a band closed in a loop, around the set of trays 3. This loop tightly surrounds the trays 3 and holds them together. Preferably, the stacking means 1 can be surrounded by at least a group of parallel straps 10. Two groups can be arranged, perpendicular to each other. The strap 10 may circulate inside the pallet 4, if applicable.

As best seen for FIG. 4, the tray 3 has a set of ribs 9, located on its walls 6. These ribs 9 work for creating a local offset between the strap 10 and the wall 6 itself. Preferably, the rib 9 is curved for holding the strap 10 in the central location. Also, preferably, the configuration for one wall 6, for one strap 10, is based on a pair of facing ribs 9. The bottom of the curved receiving surface is offset from the wall 6 itself, so that a cutting element, like a cutter or a knife, may be inserted between the two ribs 9 for opening the strap 10.

One of the advantage of having a tray 3 with a flat and smooth bottom with an openable door 7 is the possibility to transfer the products 2 with a mere planar transfer. Also, this configuration is compatible with any kind of products 2, as no referencing shape is provided, which would be adapted to the product 2 itself. Providing position means 8 further improves the stability of the stacking means 1, thereby reducing the number of straps 10 required, along with the number of corresponding strapping operations. Finally, having a pallet 4 of a design mechanically compatible with the trays 3 and able to cooperate with them, leads to a solution for storing products 2 which is significantly improved at least in terms of stability. This enhanced stability is necessary as the stacking means 1 is further moved in the industrial plant, for shipment or even temporary storage.

While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details, in addition to those discussed above, could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only, and not limiting as to the scope of the invention which is to be given the full breadth of the claims appended in any and all equivalents thereof, including any combination of their features. 

1. Stacking means (1) for shipping or storing, in which products (2) are stored in stacked layers, each layer comprising a batch of products (2), said stacking means (1) comprising a plurality of trays (3) one above the other, the sizes of said trays (3) being compatible with the dimensions of a standard shipping pallet (4), wherein each tray (3) has a rectangular base (5) on which products (2) can stand, as well as side walls (6), extending from the perimeter of said base (5) and perpendicular to it, and at least one wall (6) works as a door (7) which can be opened for allowing side introduction of the products (2) in the tray (3), or closed.
 2. Stacking means (1) according to claim 1, wherein the at least one door (7) is hinged as a flap and rotates to an axis.
 3. Stacking means (1) according to claim 1 wherein the door (7) is detachable and can be separated from the rest of the tray (3).
 4. Stacking means (1) according to claim 1, wherein each tray (3) further comprises a locking means for locking the at least one door (7) in a closed position.
 5. Stacking means (1) according to claim 4, wherein the locking means is arranged on the door (7) itself, the tray (3) being such that the products (2), once loaded in said tray (3), maintain the door (7) in a closed position.
 6. Stacking means (1) according to claim 1, wherein the tray (3) is provided with position means (8), for positioning two directly stacked trays (3) with respect to each other, said position means (8) comprising a top portion, located at the top of the tray (3), and a bottom portion, located at the bottom of the tray (3), the top portion of the position means (8) of a first tray (3) being able to cooperate with the bottom portion of the position means (8) of a second tray (3) resting on said first tray (3).
 7. Stacking means (1) according to claim 6, wherein it further comprises a bottom pallet (4) on which the stack of trays (3) rests and which is able to cooperate with the bottom portion of the position means (8) of the first tray (3) of said stack.
 8. Stacking means (1) according to claim 1, wherein the tray (3) has ribs (9) located at the outer side of two facing walls (6), for receiving a strap (10) surrounding the stack of trays (3).
 9. Stacking means (1) according to claim 1, wherein, the tray (3) comprises products (2) standing on its base (5), and the walls (6) are such that the above tray (3) rests on the products (2).
 10. Stacking means (1) according to claim 1, wherein the tray (3) has a unique identification means.
 11. Tray (3) for a stacking means (1) according to claim
 1. 12. Stacking means (1) according to claim 2, wherein each tray (3) further comprises a locking means for locking the at least one door (7) in a closed position.
 13. Stacking means (1) according to claim 3, wherein each tray (3) further comprises a locking means for locking the at least one door (7) in a closed position.
 14. Stacking means (1) according to claim 2, wherein the tray (3) is provided with position means (8), for positioning two directly stacked trays (3) with respect to each other, said position means (8) comprising a top portion, located at the top of the tray (3), and a bottom portion, located at the bottom of the tray (3), the top portion of the position means (8) of a first tray (3) being able to cooperate with the bottom portion of the position means (8) of a second tray (3) resting on said first tray (3).
 15. Stacking means (1) according to claim 3, wherein the tray (3) is provided with position means (8), for positioning two directly stacked trays (3) with respect to each other, said position means (8) comprising a top portion, located at the top of the tray (3), and a bottom portion, located at the bottom of the tray (3), the top portion of the position means (8) of a first tray (3) being able to cooperate with the bottom portion of the position means (8) of a second tray (3) resting on said first tray (3).
 16. Stacking means (1) according to claim 4, wherein the tray (3) is provided with position means (8), for positioning two directly stacked trays (3) with respect to each other, said position means (8) comprising a top portion, located at the top of the tray (3), and a bottom portion, located at the bottom of the tray (3), the top portion of the position means (8) of a first tray (3) being able to cooperate with the bottom portion of the position means (8) of a second tray (3) resting on said first tray (3).
 17. Stacking means (1) according to claim 5, wherein the tray (3) is provided with position means (8), for positioning two directly stacked trays (3) with respect to each other, said position means (8) comprising a top portion, located at the top of the tray (3), and a bottom portion, located at the bottom of the tray (3), the top portion of the position means (8) of a first tray (3) being able to cooperate with the bottom portion of the position means (8) of a second tray (3) resting on said first tray (3).
 18. Stacking means (1) according to claim 2, wherein the tray (3) has ribs (9) located at the outer side of two facing walls (6), for receiving a strap (10) surrounding the stack of trays (3).
 19. Stacking means (1) according to claim 3, wherein the tray (3) has ribs (9) located at the outer side of two facing walls (6), for receiving a strap (10) surrounding the stack of trays (3).
 20. Stacking means (1) according to claim 4, wherein the tray (3) has ribs (9) located at the outer side of two facing walls (6), for receiving a strap (10) surrounding the stack of trays (3). 